Sphincterotome with stiffening member

ABSTRACT

A sphincterotome is disclosed including an elongate shaft having a lumen extending through at least a portion of the elongate shaft. The lumen includes a proximal segment and a distal segment. A cutting element extends within the lumen through the proximal segment of the lumen and extends exterior of the elongate shaft along the distal segment of the lumen. A stiffening member is positioned within the distal segment of the lumen.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. application Ser.No. 11/557,706, now U.S. Pat. No. 7,766,909, filed Nov. 8, 2006, theentire disclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention pertains generally to medical devices and moreparticularly to medical devices such as sphincterotomes useful inperforming diagnostic and therapeutic modalities in an anatomy, such asthe biliary tree.

BACKGROUND

In medical procedures such as endoscopic sphincterotomy, asphincterotome may be used in conjunction with an endoscope to providesurgical cutting inside of a patient. Exemplary sphincterotomes aredisclosed in commonly assigned U.S. Pat. No. 6,743,217 to Rowland et al.and U.S. Pat. No. 6,579,300 to Griego et al., the disclosures of whichare incorporated herein by reference. The sphincterotome may, forexample, be directed through the duodenum to the sphincter of Oddi. Thesphincterotome may then be used to partially incise the sphincter musclefor treatment such as removal of common bile duct stones forming anobstruction within a bile duct. A sphincterotome may include a cuttingwire that can be activated by bending the sphincterotome, therebypermitting an exposed portion of the cutting wire to form a chordextending between two points along the distal portion of thesphincterotome.

However, when activating the cutting wire, it may be difficult tocontrol the exact positioning of the cutting wire. In some instances, itmay be desirable to position the activated cutting wire in an angularconfiguration commonly referred to in the art as the “12 o′clock”position, or in any other desirable angular configuration. Additionally,the tip portion of the sphincterotome may be prone to kinking orwhipping when the cutting wire is actuated.

There remains a need, therefore, for an improved sphincterotome that isconfigured such that, when activated, the cutting wire assumes a desiredcutting position at or near the “12 o′clock” position, or any otherdesired angular configuration. A need remains for an improvedsphincterotome with controlled bending characteristics which improvesorientation, bowing, cutting, and/or rigidity, and/or reduces kinkingand/or whipping of the tip during a medical procedure.

SUMMARY

The disclosure is directed to a sphincterotome including an elongateshaft, a cutting element, and a stiffening member positioned within alumen of the distal region of the elongate shaft.

Accordingly, one illustrative embodiment is a sphincterotome includingan elongate shaft having a cutting element lumen and a guidewire lumeneach extending through at least a portion of the elongate shaft. Thesphincterotome also includes a cutting element, wherein a portion of thecutting element is disposed within the cutting element lumen and aportion of the cutting element lumen is disposed exterior to the cuttingelement lumen such that a portion of the length of the cutting elementlumen is vacant of the cutting element. A stiffening member is disposedin at least a portion of the portion of the cutting element lumen vacantof the cutting element.

Another illustrative embodiment is a sphincterotome including anelongate shaft having a lumen extending through at least a portion ofthe elongate shaft. The elongate shaft includes a first side portproviding access to the lumen, and a second side port providing accessto the lumen. The second side port is located a distance from the firstside port, wherein a portion of the lumen extends between the first sideport and the second side port. The sphincterotome also includes acutting element, wherein a first portion of the cutting element extendsthrough a first segment of the lumen and a second portion of the cuttingelement extends between the first side port and the second side portexternal of the elongate shaft. A stiffening member is positioned withinat least a portion of a second segment of the lumen, wherein the secondsegment of the lumen is defined between the first side port and thesecond side port.

Yet another illustrative embodiment is a sphincterotome including anelongate shaft having a cutting element lumen and a guidewire lumen eachextending through at least a portion of the elongate shaft. The cuttingelement lumen includes a proximal segment and a distal segment. Thesphincterotome also includes a cutting element extending within thecutting element lumen through the proximal segment of the cuttingelement lumen and extending exterior of the elongate shaft along thedistal segment of the cutting element lumen. A stiffening member ispositioned within at least a portion of the distal segment of thecutting element lumen.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more completely understood in consideration of thefollowing detailed description of various embodiments in connection withthe accompanying drawings, in which:

FIG. 1 is a plan view of an exemplary sphincterotome;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is an enlarged cross-sectional view of the distal section of theexemplary sphincterotome of FIG. 1;

FIG. 3A is an enlarged cross-sectional view of the distal section of theexemplary sphincterotome of FIG. 1 in an activated, bowed configuration;

FIG. 4A is a cross-sectional view taken along line 4A-4A of FIG. 3;

FIGS. 4B-4D are alternative cross-sectional views of a distal section ofan exemplary sphincterotome;

FIG. 5 is an alternative view of a distal section of an exemplarysphincterotome;

FIG. 6 is an alternative view of a distal section of an exemplarysphincterotome;

FIG. 7 is an alternative view of a distal section of an exemplarysphincterotome;

FIG. 8 is an alternative view of a distal section of an exemplarysphincterotome; and

FIG. 9 is an alternative view of a distal section of an exemplarysphincterotome.

While the invention is amenable to various modifications and alternativeforms, specifics thereof have been shown by way of example in thedrawings and will be described in detail. It should be understood,however, that the intention is not to limit the invention to theparticular embodiments described. On the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification.

All numeric values are herein assumed to be modified by the term“about”, whether or not explicitly indicated. The term “about” generallyrefers to a range of numbers that one of skill in the art would considerequivalent to the recited value (i.e., having the same function orresult). In many instances, the term “about” may be indicative asincluding numbers that are rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4,and 5).

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The detailed description and the drawings, which are notnecessarily to scale, depict illustrative embodiments and are notintended to limit the scope of the invention. The illustrativeembodiments depicted are intended only as exemplary. Selected featuresof any illustrative embodiment may be incorporated into an additionalembodiment unless clearly stated to the contrary.

Referring now to FIG. 1, a sphincterotome 10 is generally illustrated.The sphincterotome 10 can be seen as including a proximal section 12 anda distal section 14. A handle 16 is disposed within the proximal section12 and an elongate shaft 18 extends distally therefrom. The handle 16may be formed of any suitable material, such as a metallic or polymericmaterial including, but not necessarily limited to those discussedherein.

In some embodiments, the sphincterotome 10 may include one or more hubs,such as a first hub 30 and a second hub 32, disposed in the proximalsection 12 of the sphincterotome 10. In some instances, if desired, thefirst hub 30 may include a port 31 that may be used to gain fluid accessto an interior of the elongate shaft 18. Additionally, or alternatively,if present, the second hub 32 may include a port 33, such as a guidewireport, providing guidewire access to the interior of the elongate shaft18. The hubs 30, 32 may be formed of any suitable material, such asthose materials listed elsewhere herein.

The elongate shaft 18 may be formed of or include any suitable material,such as a polymeric material. Some suitable polymeric materials include,but are not necessarily limited to, polyamide, polyether block amide,polyethylene, polypropylene, polyvinylchloride, polyurethane, andcopolymers, blends, mixtures or combinations thereof. In some cases, theelongate shaft 18 may include portions made from or includingpolytetrafluoroethylene (PTFE), commonly known as TEFLON®. The elongateshaft 18, which includes a distal region 20 and a proximal region 24,extends from a distal end 22 to a proximal end 26. The proximal end 26may extend into, be secured to or otherwise extend distally from thehandle 16, the first hub 30 and/or the second hub 32.

FIG. 2, which is a cross-section taken through the elongate shaft 18,provides an illustrative, non-limiting, example of an interior of theelongate shaft 18. As shown in FIG. 2, it can be seen that the elongateshaft 18 includes a first lumen 34, a second lumen 36 and a third lumen38. Although three lumens are illustrated in FIG. 2, it is noted that insome embodiments, the elongate shaft 18 may include only one lumen, mayinclude only two lumens, or may include additional lumens, as desired.In some embodiments, one or more of the lumens may extend from theproximal end 26 to the distal end 22 of the elongate shaft 18, or anyportion of the length of the elongate shaft 18. For instance, the firstlumen 34, which may be considered a guidewire lumen in some embodiments,may only extend through a distal portion of the elongate shaft 18.However, in other embodiments, the first lumen 34 may extend throughsubstantially the entire length of the elongate shaft 18. Furthermore,the second lumen 36, which may be considered a cutting element lumen insome embodiments, may terminate proximal of the distal end 22 of theelongate shaft 18.

In the illustrative embodiment, the first lumen 34 may, for example, bea guidewire lumen in communication with the guidewire port 33 within thesecond hub 32. The second lumen 36 may, for example, accommodate orhouse a cutting element 40. The third lumen 38, may, for example, be afluid delivery lumen, such as a contrast fluid lumen, in fluidcommunication with the port 31 of the first hub 30.

Returning to FIG. 1, the cutting element 40 may extend from the handle16 to a position within the distal region 20 of the elongate shaft 18.The cutting element 40, for example a cutting wire as known in the art,may be a multifilament wire such as a braided wire, or a monofilamentwire. The cutting wire may have a selected cross-sectional geometryincluding, for example, round, rectangular, triangular, or any othershape. It should be noted that the cutting element 40 has a distal end(discussed later with respect to FIGS. 3 and 5-9) and a proximal end 44.In some embodiments, the proximal end 44 of the cutting element 40 maybe secured to the handle 16. More particularly, in some embodiments, thehandle 16 may include a stationary portion 56 and an actuatable portion58. The stationary portion 56 of the handle 16 may be secured to theelongate shaft 18, while the proximal end 44 of the cutting element 40may be secured to the actuatable portion 58 of the handle 16. In someembodiments, the actuatable portion 58 may be slidably disposed on thestationary portion 56, such that the actuatable portion 58 may beslidably actuated relative to the stationary portion 56. In otherembodiments, the cutting element 40 may be actuated (e.g.,longitudinally translated relative to the elongate shaft 18) by othermeans.

The stationary portion 56 may, in some embodiments, include a thumb ring50 while the actuatable portion 58 may include one or more finger rings52. Thus, in such embodiments, the physician or other operator mayactivate the sphincterotome 10 by holding the thumb ring 50 in his/herthumb and using his/her fingers to manipulate the finger rings 52, andthus the actuatable portion 58. Manipulation of the finger rings 52actuates the cutting element 40 proximally and/or distally (e.g.,longitudinal translation) relative to the elongate shaft 18 such that anexposed portion of the cutting element 40 forms a chord between twopoints along the distal region 20 of the elongate shaft 18.

The handle 16 may also, in some embodiments, include a connector block90 that may be used to provide communication between the cutting element40 and an energizing source, such as an RF heating source, as is knownin the art, in order to stimulate the cutting element 40.

The distal region 20 of the elongate shaft 18 may, as illustrated,include one or more radiopaque markers such as marker bands 54. Themarker bands 54, if present, may be formed of any suitable radiopaquematerial and may have any appropriate dimensions and/or axial spacing,as desired. The marker bands 54 may aid in positioning thesphincterotome 10 during a medical procedure. Alternatively, thecatheter may include a radiopaque filler within the materials forming atleast a portion of the catheter.

FIG. 3 is an enlarged cross-sectional view of the distal section 14 ofthe sphincterotome 10. As shown in FIG. 3, a guidewire 60 is shownextending through the first lumen 34. The guidewire 60 may facilitatenavigation and/or placement of the sphincterotome 10 within the anatomyof a patient during a medical procedure.

The distal region 20 of the elongate shaft 18 may include a first sideport 70 and a second side port 72. The first side port 70 may provideaccess through the wall of the elongate shaft 18 to the second lumen 36.Similarly, the second side port 72 may provide access through the wallof the elongate shaft 18 to the second lumen 36. The first side port 70may be positioned a distance proximal of the second side port 72,wherein the second lumen 36 continues between the first side port 70 andthe second side port 72. In some embodiments the first side port 70 maybe about 5 millimeters or more, about 10 millimeters or more, about 20millimeters or more, or about 30 millimeters or more proximal of thesecond side port 72. For example, in some embodiments, the first sideport 70 may be about 5, 10, 15, 20, 25, 30, 35, or 40 millimetersproximal of the second side port 72. Thus, the length of the segment ofthe second lumen 36 spanning the first side port 70 and the second sideport 72 may have a corresponding length. Although some suitabledimensions are disclosed, one of skill in the art would understand thatdesired dimensions may deviate from those expressly disclosed.

The placement of the cutting element 40 may be further described whilereferring to FIG. 3. The cutting element 40 may extend within the secondlumen 36 through a portion of the elongate shaft 18 just proximal of thefirst side port 70. The cutting element 40 may then exit the secondlumen 36 at the first side port 70 and continue distally exterior of theelongate shaft 18, such that the second lumen 36 is vacant of thecutting element 36 through a portion of the length of the second lumen36. The cutting element 40 may reenter the elongate shaft 18 at thesecond side port 72. Therefore, the portion of the cutting element 40extending between the first side port 70 and the second side port 72external of the second lumen 36 may constitute an exposed portion 46 ofthe cutting element 40.

A stiffening member 80 may be positioned within at least a portion ofthe length of the segment of the second lumen 36 vacant of the cuttingelement 40. The stiffening member 80 may have a proximal end 82 and adistal end 84. In some embodiments, the proximal end 82 of thestiffening member 80 may be proximate the first side port 70 and thedistal end 84 of the stiffening member 80 may be proximate the secondside port 72. In some embodiments, the stiffening member 80 may bedisposed in a majority of the length of the segment of the second lumen36 vacant of the cutting element 40. In other embodiments, thestiffening member 80 may be disposed in a substantial portion of thelength of the segment of the second lumen 36 vacant of the cuttingelement 40. In some embodiments, the stiffening member 80 may bedisposed in 25% or more, 40% or more, 50% or more, 60% or more, 75% ormore, or 90% or more of the length of the segment of the second lumen 36vacant of the cutting element 40. For example, in some embodiments, thestiffening member 80 may have a length of about 10 to about 20millimeters and the length of the second lumen 36 vacant of the cuttingelement 40 may be about 20 millimeters. In other embodiments, thestiffening member 80 may have a length of about 20 to about 30millimeters and the length of the second lumen 36 vacant of the cuttingelement 40 may be about 30 millimeters. Thus, in some embodiments, thestiffening member 80 may extend parallel with the exposed portion 46 ofthe cutting element 40 and/or the stiffening member 80 may extend alonga common longitudinal length with the exposed portion 46 of the cuttingelement 40.

In some embodiments, the distal end 42 of the cutting element 40 may besecured to the stiffening member 80. For example, the cutting element 40may be secured to the stiffening member 80 by welding, brazing,soldering, adhesive bonding, fusion bonding, crimping, mechanicalfastening, twisting, looping, bending, or the like. Thus, in someembodiments, the stiffening member 80 may act as an anchor for thedistal end 42 of the cutting element 40.

In some embodiments, the stiffening member 80 may be a solid member, asshown in FIG. 3, or, in other embodiments, the stiffening member 80 maybe a tubular member or a filler of material, for example. For instance,the stiffening member 80 shown in FIG. 3 may be a solid wire. Thestiffening member 80 may be formed of any suitable material. Somesuitable materials include metals such as stainless steel alloys, andshape memory alloys, such as nickel-titanium alloys, some of which arecommonly referred to as nitinol. Some suitable polymers include thosepolymers listed herein, as well as shape memory polymers. One of skillin the art would understand that other undisclosed materials may besuitable in forming the stiffening member 80.

Stiffening member 80 may be designed to adhere well with the cathetermaterial. Alternatively, adhesives, melting or a tie layer can be used.The surface of member 80 may be etched, scraped or roughened to improveconnection to the catheter. Stiffening member 80 may further includeapertures, slots, bumps, dents and combinations thereof to aidattachment and control flexibility of the stiffening member 80.

The exposed portion 46 of the cutting element 40 and/or the stiffeningmember 80 may be subjected to a cold-forming process to provide desiredcharacteristics to the cutting element 40 and/or the stiffening member80. For example, the stiffening member 80 may be subjected to acold-forming process imparting a preformed curvature to the stiffeningmember 80. The preformed curvature of the stiffening member 80 mayprovide the cutting element 40 with a predictable orientation, such as a“12 o′clock” position as known in the art. Additionally, the preformedcurvature of the stiffening member 80 may provide the distal portion ofthe elongate shaft 18 with a more uniform bowed configuration, withoutkinking, when the cutting element 40 is actuated proximally duringoperation. FIG. 3A is a cross-sectional view of the distal section 14 ofthe sphincterotome 10 assuming a bowed or curved position, such as whenthe cutting element 40 is activated by pulling the cutting element 40proximally through the manipulation of the handle 16. As shown in FIG.3A, when the cutting element 40 is activated, the exposed portion 46 ofthe cutting element 40 may form a chord between two points (e.g., thefirst side port 70 and the second side port 72) along the curved distalregion 20 of the elongate shaft 18.

In embodiments where the stiffening member 80 includes a shape memorymaterial, such as a shape memory alloy or a shape memory polymer, thestiffening member 80 may be configured to have a first shape and asecond shape. Shape memory materials are those materials which arecharacterized by their responsiveness to thermal stimulus in order totransform between a first shape and a second shape. For example, thefirst shape may be a straight configuration and the second shape may bea curved configuration. The stiffening member 80 formed of a shapememory material may be programmed to transition from a straightconfiguration to a curved configuration at a predetermined temperature,for example a temperature just below the body temperature of a patient.In some embodiments, the predetermined temperature may be in the rangeof 70° F. to about 98° F., or in the range of 80° F. to about 95° F., orin the range of about 90° F. to about 95° F. In other words, thestiffening member 80 may assume a first shape at temperatures below thepredetermined temperature, and may assume a second shape at temperaturesabove the predetermined temperature. In embodiments wherein thepredetermined temperature is chosen to be at or below the bodytemperature of a patient, the stiffening member 80 may assume a first,straight configuration external of the body of the patient, but maytransition to a second, curved configuration upon reaching thepredetermined temperature within the body of the patient. Alternatively,the change in shape may be actuated by infusion of a warm fluid. Thestiffening member 80 may be positioned in the distal section 20 of theelongate shaft 18 such that the bending plane of the stiffening member80 in the curved configuration provides the cutting element 40 with apredictable orientation, such as a “12 o′clock” position, during amedical procedure.

FIG. 4A is a cross-sectional view through the distal section 14 of theelongate shaft 18. As shown in FIG. 4A, the stiffening member 80 mayhave a circular cross-section. The cross-section of the stiffeningmember 80 may substantially fill the second lumen 36, or thecross-section of the stiffening member 80 may occupy any portion of thesecond lumen 36. In some embodiments, the cross-section of thestiffening member 80 may be substantially similar to the cross-sectionof the cutting element 40.

FIGS. 4B-4D illustrate alternative embodiments of the cross-section ofthe stiffening member 80. FIG. 4B illustrates the stiffening member 80as having an oval cross-section, FIG. 4C illustrates the stiffeningmember 80 as having a flattened or rectangular cross-section, and FIG.4D illustrates the stiffening member 80 as having a semi-circularcross-section. The cross-sections illustrated in FIGS. 4B-4D, resultantof their respective moments of inertia (i.e., second moment of area) atthe centroid of the cross-section, may provide the stiffening member 80with a preferred bending plane, thus providing the cutting element 40with a predictable orientation, such as a “12 o′clock” position, duringoperation.

In some embodiments, such as the illustrative embodiment of FIG. 3, thesecond lumen 36 terminates proximal of the distal end 22 of the elongateshaft 18. In such embodiments, at an intermediate stage of manufacture,the second lumen 36 may extend to the distal end 22 of the elongateshaft 18. The cross-section of the lumen may be made to complement thecross-section of the stiffening member. Therefore, the stiffening member80 may be positioned within the second lumen 36 from the distal end 22of the elongate shaft 18. Subsequently, the distal end 22 of theelongate shaft 18 may be subjected to a process wherein the extremedistal portion of the second lumen 36 is collapsed, filled, or otherwiseoccluded. For example, the distal end 22 of the elongate shaft 18 may beheated forming a molded distal tip 25, such that the extreme distalportion of the second lumen 36 is collapsed or closed off.Alternatively, the extreme distal portion of the second lumen 36 may befilled with a polymeric material, an adhesive, or other suitablematerial such that the extreme distal portion of the second lumen 36 isoccluded.

An alternative embodiment of a distal section 114 of the sphincterotome10 is shown in FIG. 5. The distal section 114 illustrated in FIG. 5 issimilar to the distal section 14 illustrated in FIG. 3, with theexception of certain aspects concerning the stiffening member 180. Thus,for the sake of repetitiveness, similarities of the distal section 114with those of the distal section 14 will not be repeated.

The stiffening member 180, as shown in FIG. 5, may be a tubular memberhaving a proximal end 182 and a distal end 184. The proximal end 182 maybe positioned proximate the first side port 70 and the distal end 184may be positioned proximate the second side port 72. In someembodiments, the stiffening member 180 may be disposed in a majority ofthe length of the segment of the second lumen 36 vacant of the cuttingelement 40. In other embodiments, the stiffening member 180 may bedisposed in a substantial portion of the length of the segment of thesecond lumen 36 vacant of the cutting element 40. The tubular member mayprovide the stiffening member 180 with stiffening characteristics whileretaining a passageway therethrough. The distal end 42 of the cuttingelement 40 may be secured to the stiffening member 180 proximate thesecond side port 72. Other aspects of the stiffening member 180 may besimilar to those discussed above regarding the stiffening member 80.Therefore, for the sake of repetitiveness, notable similarities will notbe repeated. For example, the stiffening member 180 may be subjected toa cold-forming process, may be formed of a shape memory material, or mayhave a cross-section providing the stiffening member 180 with apreferred bending plane, thus providing the cutting element 40 with apredictable orientation, such as a “12 o′clock” position, duringoperation.

An alternative embodiment of a distal section 214 of the sphincterotome10 is shown in FIG. 6. The distal section 214 illustrated in FIG. 6 issimilar to the distal section 14 illustrated in FIG. 3, with theexception of certain aspects concerning the stiffening member 280 andthe inclusion of an anchoring member 285. Thus, for the sake ofrepetitiveness, similarities of the distal section 214 with those of thedistal section 14 will not be repeated.

The stiffening member 280, as shown in FIG. 6, may be a filler ofmaterial, such as a polymeric filler or an adhesive filler, having aproximal end 282 and a distal end 284. The proximal end 282 may beproximate the first side port 70 and the distal end 284 may be proximatethe second side port 72. In some embodiments, the stiffening member 280may be disposed in a majority of the length of the segment of the secondlumen 36 vacant of the cutting element 40. In other embodiments, thestiffening member 280 may be disposed in a substantial portion of thelength of the segment of the second lumen 36 vacant of the cuttingelement 40. Other aspects of the stiffening member 280 may be similar tothose discussed above regarding the stiffening member 80. Therefore, forthe sake of repetitiveness, notable similarities will not be repeated.For example, the stiffening member 280 may be formed of a shape memorymaterial or may have a cross-section providing the stiffening member 280with a preferred bending plane, thus providing the cutting element 40with a predictable orientation, such as a “12 o′clock” position, duringoperation.

An anchoring member 285 may also be positioned in a portion of thesecond lumen 36 proximate the second side port 72. As shown in FIG. 6,the anchoring member 285 may be positioned distal of the stiffeningmember 280, for example abutting the distal end 284 of the stiffeningmember 280. In some embodiments, the anchoring member 285 may be securedto the stiffening member 280. However, in other embodiments, theanchoring member 285 may be unsecured to the stiffening member 280. Theanchoring member 285 may be formed of any suitable material, such as ametallic material or a polymeric material, including but not necessarilylimited to those materials listed herein. The distal end 42 of thecutting element 40 may be secured to the anchoring member 285 proximatethe second side port 72.

An alternative embodiment of a distal section 314 of the sphincterotome10 is shown in FIG. 7. The distal section 314 illustrated in FIG. 7 issimilar to the distal section 14 illustrated in FIG. 3, with theexception of certain aspects concerning the stiffening member 380 andthe inclusion of an anchoring member 385. Thus, for the sake ofrepetitiveness, similarities of the distal section 314 with those of thedistal section 14 will not be repeated.

The stiffening member 380, as shown in FIG. 7, may be a solid memberhaving a proximal end 382 and a distal end 384. The proximal end 382 maybe positioned proximate the first side port 70 and the distal end 384may be positioned proximate the second side port 72. In someembodiments, the stiffening member 380 may be disposed in a majority ofthe length of the segment of the second lumen 36 vacant of the cuttingelement 40. In other embodiments, the stiffening member 380 may bedisposed in a substantial portion of the length of the segment of thesecond lumen 36 vacant of the cutting element 40. Other aspects of thestiffening member 380 may be similar to those discussed above regardingthe stiffening member 80. Therefore, for the sake of repetitiveness,notable similarities will not be repeated. For example, the stiffeningmember 380 may be subjected to a cold-forming process, may be formed ofa shape memory material, or may have a cross-section providing thestiffening member 380 with a preferred bending plane, thus providing thecutting element 40 with a predictable orientation, such as a “12o′clock” position, during operation.

An anchoring member 385 may also be positioned in a portion of thesecond lumen 36 proximate the second side port 72. As shown in FIG. 7,the anchoring member 385 may be positioned distal of the stiffeningmember 380, for example abutting the distal end 384 of the stiffeningmember 380. In some embodiments, the anchoring member 385 may be securedto the stiffening member 380. However, in other embodiments, theanchoring member 385 may be unsecured to the stiffening member 380. Theanchoring member 385 may be formed of any suitable material, such as ametallic material or a polymeric material, including but not necessarilylimited to those materials listed herein. The distal end 42 of thecutting element 40 may be secured to the anchoring member 385 proximatethe second side port 72.

An alternative embodiment of a distal section 414 of the sphincterotome10 is shown in FIG. 8. The distal section 414 illustrated in FIG. 8 issimilar to the distal section 14 illustrated in FIG. 3, with theexception of certain aspects concerning the stiffening member 480. Thus,for the sake of repetitiveness, similarities of the distal section 414with those of the distal section 14 will not be repeated.

The stiffening member 480, as shown in FIG. 8, may be an extension ofthe cutting element 40. For example, as shown in FIG. 8, a portion ofthe cutting element 40 may extend within the second lumen 36 through aportion of the elongate shaft 18 just proximal of the first side port70. The cutting element 40 may then exit the second lumen 36 at thefirst side port 70 and continue distally exterior of the elongate shaft18 and may reenter the elongate shaft 18 at the second side port 72.Therefore, the portion of the cutting element 40 extending between thefirst side port 70 and the second side port 72 external of the secondlumen 36 may constitute an exposed portion 46 of the cutting element 40.The cutting element 40 may be doubled back upon itself such that afterreentering the elongate shaft 18 through the second side port 72 aportion of the cutting element 40 extends from the second side port 72proximally through the second lumen 36 toward the first side port 70.The portion of the cutting element 40 extending within the second lumen36 between the second side port 72 and the first side port 70 may definethe stiffening member 480. This portion of the stiffening member 80 canhave any selected cross-sectional geometry as discussed above. In someembodiments, the end of the stiffening member 480 (i.e., the distal end42 of the cutting element 40) may be positioned proximate the first sideport 70. In some embodiments, the stiffening member 480 may be disposedin a majority of the length of the segment of the second lumen 36between the second side port 72 and the first side port 70. In otherembodiments, the stiffening member 480 may be disposed in a substantialportion of the length of the segment of the second lumen 36 between thesecond side port 72 and the first side port 70.

Other aspects of the stiffening member 480 may be similar to thosediscussed above regarding the stiffening member 80. Therefore, for thesake of repetitiveness, notable similarities will not be repeated. Forexample, the stiffening member 480 may be subjected to a cold-formingprocess, may be formed of a shape memory material, or may have across-section providing the stiffening member 480 with a preferredbending plane, thus providing the cutting element 40 with a predictableorientation, such as a “12 o′clock” position, during operation.

An alternative embodiment of a distal section 514 of the sphincterotome10 is shown in FIG. 9. In many respects, the distal section 514illustrated in FIG. 9 is similar to the distal section 14 illustrated inFIG. 3, with the exception that a distal portion 520 of the elongateshaft 18 includes a reduced diameter relative to a more proximal portion518. Thus, for the sake of repetitiveness, similarities of the distalsection 514 with those of the distal section 14 will not be repeated. Itis noted that the terms “proximal” and “distal” in describing theportions of the elongate shaft 18 are intended to describe the relativespatial relationship between the proximal portion 518 and the distalportion 520.

As shown in FIG. 9, the proximal portion 518 of the elongate shaft 18may have an outer diameter and the distal portion 520 of the elongateshaft 18 may have an outer diameter less than the outer diameter of theproximal portion 518. A tapered portion 519 may be positionedintermediate the proximal portion 518 and the distal portion 520providing a transition between the proximal portion 518 and the distalportion 520. The reduced diameter or drawn-down distal portion 520 mayprovide the elongate shaft 18 with increased flexibility and/ormaneuverability such that the sphincterotome 10 may be advanced throughmore tortuous and/or narrower pathways.

A portion of the cutting element 40 may extend within the second lumen36 through a portion of the elongate shaft 18 just proximal of the firstside port 70. The cutting element 40 may then exit the second lumen 36at the first side port 70 and continue distally exterior of the elongateshaft 18 and may reenter the elongate shaft 18 at the second side port72. Therefore, the portion of the cutting element 40 extending betweenthe first side port 70 and the second side port 72 external of thesecond lumen 36 may constitute an exposed portion 46 of the cuttingelement 40.

A stiffening member 580 may be positioned within at least a portion ofthe length of the segment of the second lumen 36 vacant of the cuttingelement 40. The stiffening member 580 may have a proximal end 582 and adistal end 584. In some embodiments, the proximal end 582 of thestiffening member 580 may be proximate the first side port 70 and thedistal end 584 of the stiffening member 580 may be proximate the secondside port 72. In some embodiments, the stiffening member 580 may bedisposed in a majority of the length of the segment of the second lumen36 vacant of the cutting element 40. In other embodiments, thestiffening member 580 may be disposed in a substantial portion of thelength of the segment of the second lumen 36 vacant of the cuttingelement 40.

Other aspects of the stiffening member 580 may be similar to thosediscussed above regarding the stiffening member 80. Therefore, for thesake of repetitiveness, notable similarities will not be repeated. Forexample, the stiffening member 580 may be subjected to a cold-formingprocess, may be formed of a shape memory material, or may have across-section providing the stiffening member 580 with a preferredbending plane, thus providing the cutting element 40 with a predictableorientation, such as a “12 o′clock” position, during operation.

Although an exemplary embodiment(s) of a sphincterotome has beendisclosed, it is noted that alternate designs may be included. Forexample, the various lumens of a design may be made in fluidcommunication with one another to aid in fluid infusion.

Those skilled in the art will recognize that the present invention maybe manifested in a variety of forms other than the specific embodimentsdescribed and contemplated herein. Accordingly, departure in form anddetail may be made without departing from the scope and spirit of thepresent invention as described in the appended claims.

What is claimed is:
 1. An electrosurgical cutting device comprising: anelongate shaft having a proximal end and a distal end, the elongateshaft including: a first lumen extending to the distal end of theelongate shaft; a second lumen terminating proximal of the distal end ofthe elongate shaft; a first side port extending through a sidewall ofthe elongate shaft at a location intermediate the proximal and distalends of the elongate shaft, the first side port in communication withthe second lumen; and a second side port extending through a sidewall ofthe elongate shaft at a location intermediate the first side port andthe distal end of the elongate shaft, the second side port incommunication with the second lumen; a cutting element extending throughthe second lumen proximal of the first side port and extending exteriorof the elongate shaft between the first side port and the second sideport; and a stiffening member positioned in the second lumen such that aproximal end of the stiffening member is located proximal of the secondside port and a distal end of the stiffening member is located distal ofthe second side port, wherein the stiffening member has a solidcross-section which substantially fills the second lumen.
 2. Theelectrosurgical cutting device of claim 1, wherein the stiffening memberextends parallel with a portion of the cutting member extending exteriorof the elongate shaft between the first side port and the second sideport.
 3. The electrosurgical cutting device of claim 1, wherein thecross-section of the stiffening member is substantially similar to across-section of the cutting element.
 4. The electrosurgical cuttingdevice of claim 1, wherein the stiffening member does not occupy anyportion of the second lumen proximal of the first side port.
 5. Theelectrosurgical cutting device of claim 1, wherein the second lumen hasa length measured between the first side port and the second side port,and the stiffening member extends a majority of the length.
 6. Theelectrosurgical cutting device of claim 1, wherein the proximal end ofthe stiffening member is positioned proximate the first side port. 7.The electrosurgical cutting device of claim 1, wherein the cuttingelement is secured to the stiffening member proximate the second sideport.
 8. The electrosurgical cutting device of claim 1, wherein thestiffening member is a portion of the cutting element extendingproximally from the second side port.
 9. The electrosurgical cuttingdevice of claim 1, wherein the stiffening member is a polymeric filler.10. A sphincterotome comprising: an elongate shaft having a proximal endand a distal end; a lumen extending through at least a portion of theelongate shaft; a first side port extending through a sidewall of theelongate shaft at a location intermediate the proximal and distal endsof the elongate shaft, the first side port in communication with thelumen; a second side port extending through a sidewall of the elongateshaft at a location intermediate the first side port and the distal endof the elongate shaft, the second side port in communication with thelumen; a cutting element extending through the lumen proximal of thefirst side port and extending exterior of the elongate shaft between thefirst side port and the second side port; and a stiffening memberpositioned in the lumen such that a proximal end of the stiffeningmember is located proximal of the second side port and a distal end ofthe stiffening member is located distal of the second side port; whereinthe stiffening member does not occupy any portion of the lumen proximalof the first side port.
 11. The sphincterotome of claim 10, wherein thelumen has a length measured between the first side port and the secondside port, and the stiffening member extends a majority of the length.12. The sphincterotome of claim 10, wherein the proximal end of thestiffening member is positioned proximate the first side port.
 13. Thesphincterotome of claim 10, wherein the cutting element is secured tothe stiffening member proximate the second side port.
 14. Thesphincterotome of claim 10, wherein the stiffening member is a portionof the cutting element extending proximally from the second side port.15. The sphincterotome of claim 10, wherein the stiffening member is apolymeric filler.
 16. The sphincterotome of claim 10, wherein thestiffening member is a tubular member.
 17. The sphincterotome of claim10, wherein the stiffening member includes a shape memory material.